How Accurate Tpms Tire Monitor

[macguy]

On my truck, I can see tire pressure for each tire via DIC. Today I made all 4 tires same pressure, 60psi cold at 35 degrees F. Yet my DIC after a few miles reads 56&57psi front and 57&58 rear. Is my guage off, or is the built in pressure monitor not accurate?

[thearborbarber]

Your tire gauge is better than the tpms as far as accuracy. The TPMS wasn't meant to replace a good tire gauge. It will get you in the ball park however. It's kind of like the volt gauge on the dash. Not as accurate as a volt meter but good enough to let you know there is problem.

 

Also my TPMS reads about 2-3 psi lower than my tire gauge.

[RyanbabZ71]

off by 2-3 psi, really drives me nuts. If its not going to be closer than that then why put it on? This is at 35 psi so I am seeing around 10% error.

[minibike132]

I used to think it was that far off but after I bought a very good pretty expensive digital inflator, comparing it to my electronic TPMS tools and looking at the dic they are never more then 1lb off. Most of GM's specs show +/-1to2 lb accuracy. I don't find 1lb to be objectionable. 3 might be but in my experience it is your gauge not your vehicles.

 

 

Edit: http://www.matcotools.com/Catalog/toolcata...ect=&page=4

 

This is the inflator I have and the TPMS tools I have are both the GM tool and an aftermarket tool that both read the same on every tire every time. The accuracy on this inflator is +/- 1lb so which one is right, the inflator or the dic? Either way it's only 1lb off.

[macguy]

found this,

http://www.getagauge.com/

 

wondering if they are any good?

[Matt_]

that is what ive found too... its amusing how many people think the tpms system is crap and yet i bet their gauges are +/- 3 PSI at best.

 

here's my advice: pick a gauge and stick with it and dont worry if its 2psi different than another NON CALIBRATED gauges reading!

 

and dont spend a ton of money for a fancy calibrated gauge unless you plan on having it recalibrated yearly. calibrations dont last forever....a $200 gauge thats a year out of cal isn't any better than a quality $50 pressure gauge.

 

the important part is to be consistent with what you use.

 

me personally: i use a nice quality gauge to set my pressure but base my reading off of the tpms system. its always within 2 psi of what my gauge says. by doing it this way ill also be able to identify a sensor thats going bad.....if 3 of my tires are within 2 psi of my hand gauge and 1 tire is 5psi off, then ill probably need to replace that sensor in the near future. $.02

[RyanbabZ71]

I have two tires gages I have checked it against and I am dead on each time with them both.

 

I find the error between the gages and TPMS on both my truck and tahoe.

[brims]

I use the OTC tool to pull the pressure reading off the sensor itself. The truck shows about 2 psi lower than what the actual gauge transmits. I would like to get another quality gauge to use as well. I have a $5 AutoZone gauge I leave in the truck for when I'm on the road.

[chrisb1]

Be aware if you rotate tires the TPMS units for each wheel must be retrained to the correct tire position. They are position specific to the tire and the monitor will be wrong

if the tires are rotated and the sensors are not retrained. Per Weston GMC in Gresham, Oregon.

[shocktrp]

On my truck, I can see tire pressure for each tire via DIC. Today I made all 4 tires same pressure, 60psi cold at 35 degrees F. Yet my DIC after a few miles reads 56&57psi front and 57&58 rear. Is my guage off, or is the built in pressure monitor not accurate?

 

Mine is within 1 PSI of my gauge. I also gain several pounds of pressure after the tires warm up from running on the highway.